Bubonic plague is the most common and most easily
identified form of plague. It has the following characteristics:

Incubation Period- 2-6 days.

Symptoms-

Lymphadenopathy and fever are both early symptoms of bubonic
plague.

Patients develop buboes, which are grossly enlarged, extremely
tender lymph nodes draining at the respective site of inoculation.

Progression of Disease- If bubonic
plague is not treated, the bacteria can spread through the bloodstream
causing septicemia or it can infect the lungs, causing a secondary
case of pneumonic plague. Rarely, it can progress to meningitis.